Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 8
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Book Description
Some of the most fascinating questions about the limits of nuclear stability are confronted in the heaviest nuclei. How many more new elements can be synthesized? What are the nuclear and chemical properties of these exotic nuclei? Does the 'Island of Stability' exist and can we ever explore the isotopes inhabiting that nuclear region? This paper will focus on the current experimental research on the synthesis and characterization of superheavy nuclei with Z> 112 from the Dubna/Livermore collaboration. Reactions using 48Ca projectiles from the U400 cyclotron and actinide targets ({sup 233,238}U, 237Np, {sup 242,244}Pu, 243Am, {sup 245,248}Cm, 249Cf) have been investigated using the Dubna Gas Filled Recoil Separator in Dubna over the last 8 years. In addition, several experiments have been performed to investigate the chemical properties of some of the observed longer-lived isotopes produced in these reactions. Some comments will be made on nuclear reactions used for the production of the heaviest elements. A summary of the current status of the upper end of the chart of nuclides will be presented.
Author: Matthias Schädel
Publisher: Springer Science & Business Media
ISBN: 0306484153
Category : Science
Languages : en
Pages : 324
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Book Description
This book is the first to treat the chemistry of superheavy elements, including important related nuclear aspects, as a self contained topic. It is written for those – students and novices -- who begin to work and those who are working in this fascinating and challenging field of the heaviest and superheavy elements, for their lecturers, their advisers and for the practicing scientists in the field – chemists and physicists - as the most complete source of reference about our today's knowledge of the chemistry of transactinides and superheavy elements. However, besides a number of very detailed discussions for the experts this book shall also provide interesting and easy to read material for teachers who are interested in this subject, for those chemists and physicists who are not experts in the field and for our interested fellow scientists in adjacent fields. Special emphasis is laid on an extensive coverage of the original literature in the reference part of each of the eight chapters to facilitate further and deeper studies of specific aspects. The index for each chapter should provide help to easily find a desired topic and to use this book as a convenient source to get fast access to a desired topic. Superheavy elements – chemical elements which are much heavier than those which we know of from our daily life – are a persistent dream in human minds and the kernel of science fiction literature for about a century.
Author: Valentin Matveevich Gorbachev
Publisher: Pergamon
ISBN:
Category : Science
Languages : en
Pages : 472
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Book Description
Author: Kit Chapman
Publisher: Bloomsbury Publishing
ISBN: 1472953916
Category : Science
Languages : en
Pages : 277
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Book Description
Shortlisted for the 2020 AAAS/Subaru SB&F Prize for Excellence in Science Books Creating an element is no easy feat. It's the equivalent of firing six trillion bullets a second at a needle in a haystack, hoping the bullet and needle somehow fuse together, then catching it in less than a thousandth of a second – after which it's gone forever. Welcome to the world of the superheavy elements: a realm where scientists use giant machines and spend years trying to make a single atom of mysterious artefacts that have never existed on Earth. From the first elements past uranium and their role in the atomic bomb to the latest discoveries stretching our chemical world, Superheavy will reveal the hidden stories lurking at the edges of the periodic table. Why did the US Air Force fly planes into mushroom clouds? Who won the transfermium wars? How did an earthquake help give Japan its first element? And what happened when Superman almost spilled nuclear secrets? In a globe-trotting adventure that stretches from the United States to Russia, Sweden to Australia, Superheavy is your guide to the amazing science filling in the missing pieces of the periodic table. By the end you'll not only marvel at how nuclear science has changed our lives – you'll wonder where it's going to take us in the future.
Author: Glenn T. Seaborg
Publisher: John Wiley & Sons
ISBN: 0471890626
Category : Science
Languages : en
Pages : 386
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Book Description
Written by Glenn T. Seaborg, Nobel Laureate and pre-eminent figure in the field, with the assistance of Walter D. Loveland, it covers all aspects of transuranium elements, including their discovery, chemical properties, nuclear properties, nuclear synthesis reactions, experimental techniques, natural occurrence, superheavy elements, and predictions for the future. Published on the fiftieth anniversary of the discovery of transuranium elements, it conveys the essence of the ideas and distinctive blend of theory and experiment that has marked their study.
Author: Krishna Kumar
Publisher: CRC Press
ISBN:
Category : Art
Languages : en
Pages : 176
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Book Description
Provides a review of the experimental & theoretical investigations of superheavy elements, especially their nuclear aspects. Also presents many new theoretical aspects & predictions of the Dynamic Deformation Model, developed by the author. Specific heavy-ion fusion experiments, which may lead to the discovery of superheavy elements, are suggested.
Author: W. M. Good
Publisher:
ISBN:
Category : Delayed neutrons
Languages : en
Pages : 10
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Author: Helge Kragh
Publisher: Springer
ISBN: 3319758136
Category : Science
Languages : en
Pages : 109
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Book Description
The story of superheavy elements - those at the very end of the periodic table - is not well known outside the community of heavy-ion physicists and nuclear chemists. But it is a most interesting story which deserves to be known also to historians, philosophers, and sociologists of science and indeed to the general public. This is what the present work aims at. It tells the story or rather parts of the story, of how physicists and chemists created elements heavier than uranium or searched for them in nature. And it does so with an emphasis on the frequent discovery and naming disputes concerning the synthesis of very heavy elements. Moreover, it calls attention to the criteria which scientists have adopted for what it means to have discovered a new element. In this branch of modern science it may be more appropriate to speak of creation instead of discovery. The work will be of interest to scientists as well as to scholars studying modern science from a meta-perspective.
Author: Jerome Hudis
Publisher:
ISBN:
Category : Nuclear reactions
Languages : en
Pages : 46
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Book Description
The literature has been searched for references pertaining to high energy reactions of interest to nuclear chemists. Nuclear Science Abstracts was the main source of references and wherever possible the complete abstract was retained.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 6
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Book Description
This project consisted of three major research areas: (1) development of a solid Pu ceramic target for the MASHA separator, (2) chemical separation of nuclear decay products, and (3) production of new isotopes and elements through nuclear reactions. There have been 16 publications as a result of this project, and this collection of papers summarizes our accomplishments in each of the three areas of research listed above. The MASHA (Mass Analyzer for Super-Heavy Atoms) separator is being constructed at the U400 Cyclotron at the Flerov Laboratory of Nuclear Reactions in Dubna, Russia. The purpose of the separator is to physically separate the products from nuclear reactions based on their isotopic masses rather than their decay characteristics. The separator was designed to have a separation between isotopic masses of ±0.25 amu, which would enable the mass of element 114 isotopes to be measured with outstanding resolution, thereby confirming their discovery. In order to increase the production rate of element 114 nuclides produced via the 244Pu+48Ca reaction, a new target technology was required. Instead of a traditional thin actinide target, the MASHA separator required a thick, ceramic-based Pu target that was thick enough to increase element 114 production while still being porous enough to allow reaction products to migrate out of the target and travel through the separator to the detector array located at the back end. In collaboration with UNLV, we began work on development of the Pu target for MASHA. Using waste-form synthesis technology, we began by creating zirconia-based matrices that would form a ceramic with plutonium oxide. We used samarium oxide as a surrogate for Pu and created ceramics that had varying amounts of the starting materials in order to establish trends in material density and porosity. The results from this work are described in more detail in Refs. [1,4,10]. Unfortunately, work on MASHA was delayed in Russia because it was found that the efficiency of transporting products from the target chamber to the detector array was much too low for applications in heavy element experiments where production rates are on the order of one atom per day or less. Work continues on the MASHA separator, and once the efficiency has been improved, we plan to continue our work on the Pu target for future element 114 experiments. Due to the delays of the MASHA separator, work on establishing the identity of heavy element species produced through nuclear reactions focused instead on chemical separations. In particular, element 115 decays through a series of alpha decays, terminating with an element 105 isotope with a long half-life ((almost equal to) 1 day). By chemically separating the element 105 daughter and observing its subsequent fission decay, the identity of the original parent nucleus can be established through the genetic correlation of the initial series of alpha decays. Chemical separations of element 105 were developed in Switzerland, Russia, and at LLNL. Over the course of two experiments, reaction products from the 243Am+48Ca reaction were collected in a copper block and subsequently processed for chemical separation of the Group Five elements [8,9,13,15]. The Group Five elements were initially separated from the Group Four species, and then the samples were sub-divided into tantalum and niobium fractions. All of the fission events were observed in the tantalum fractions, which implied that element 105 behaved more like tantalum under the chemical conditions of these experiments. These experiments were very successful, and not only demonstrated that chemical separation could be performed on single atoms of interest, but also lent proof to the identity of the parent nucleus as element 115. Subsequent analysis of the alpha spectra taken during the experiment further prove that the fission events observed during the two experiments came from element 105 as the decay daughter of element 115 and could not attributed to interference from other background species [16]. The final aspect of this project was the production of new isotopes and elements. All of the experiments were performed in Dubna at the U400 Cyclotron and the results are described in more detail in Refs. [2,3,5-8,11,12,14]. The first experiments were designed to establish the decay properties of isotopes of elements 112, 114, and 116 [5]. Because these isotopic signatures were established through these initial experiments, the discovery of element 118 [11] was possible, since the 118 nuclides decayed into these previously studied isotopes. This was the first successful report of the discovery of element 118, which was reported by the media to a large extent. The last experiment that was performed for this project was the production and detection of a new isotope of element 113 [14].
